Improvement in separating fibers of straw



ilnrrnn States @PATENT rrr Azeri s. LYMAN, or` New YORK, N. Y.

Specification forming part of Letters Patent No. 40,696,

To all whom/ t may concern.' c

Be it known that l, AZEL S. LYMAN, ofthe city, county, and State of New York, have invented certain new and useful improvements in the separation of the bers of straw, wood, and other vegetable substances, and extracting the gummy and coloring matters therefrom to render them iit for paper-stock and for other purposes; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification.

This invention relates to the separation of the iibers of vegetable substances and the eX- traction of their gummy and coloring matters by subjecting them to the action of water brought to a temperature atwhicli it boils under a pressure greater than that of the atv mosphcre, either with or wit-hout the use ot' alkalies or oi" rubbing, grinding, or beating devices as an aid to maceration. In such method of separation, as heretofore practiced, the boiler or maceratin g apparatus has been charged while at a temperature below 2l20 Fahrenheit, and after closing it the charge has been heated to a temperature of from 3000 to 3500 Fahrenheit, at which it has been kept for a sufficient time to effect complete maceration, and then the apparatus has been completely discharged and recharged for a new operation. The process conducted in this way involves the loss of all the time occupied in discharging and recharging, and in heating up again from below 2120 Fahrenheit to the much higher temperature required, andthe Waste of all the heat contained in the matter at the time of its discharge, which takes place at the high temperature above mentioned.

The object of'this invention is to obviate this loss of time and waste ofheat.

The invention consists in effecting the macerating process without interruption by supplying and discharging the material and the water necessary to effect maceration in a coutinuous manner by means of a forced circulation through the boiler or macerating apparatus, effected by a pump or other equivaent forcing apparatus.

It also consists in saving the heat of the discharging pulp or macerated material by retaining it under pressure after it has left the boiler or macerating apparatus, and passdated November 24, 1805 ing the incoming fibrous materia in a contrary direction to the through a suitable system of pi sages properly arranged in contar relation to the discharge pipes or It also consists in forcing the terial through a mill or other gril bing, or beating apparatus empl( nection with the boiler as an aid tion, by the combined or simultar ofthe pump or forcing apparatu: the forced circulation through t produced, and ofthe pressure due ofthe steam or water in the boiler It also consists in the construe forcing-pump by which the forced through the boiler or macerating is produced, with sharp-edged v: plied and operated as to eut an` other material which may be left i: passages when the valves close, a surethe perfect closing of the valv vent leakage.

It further consists in the empli the purpose of transferring the he: discharging pulp or macerated mat incoming material and water, of twin pipes, or, in other words, pip ing two passages through which 1 ated material and the incoming m; water can flow side by side in opp( tions. l

Figure l in the drawings is a plai paratus which embraces or illustrat era-l features of my invention. l transverse vertical section of the s plane indicated by the line x a: in Fi 3 is a central vertical section of tl pump audits appendages, for fet producing a continuous circulatie the macerating apparatus.

Similar letters of reference indi spondin g parts in the several figure The boiler represented is comp train of pipes, AA, arranged vin twt above another, in a suitable turna so connected that there may be a t through the whole series, first thi after another of the lower tier, nex one after another ofthe upper tier. pipe of the lower tier, which is the l extremeleft of the tier, and numbere 2, is connected by a pipe, G, with 4 the train.

the train of twin or double pipes F F, in which the incoming fibrous material and water are heated by the outgoing pulp or macerated material before entering the boiler, and the last pipe of the upper tier, which is the one at the extreme right of the tier, and numbered 16 in Fig. 2, is connected with the mill H, Fig. 1, by which the iibrous substances, after having been boiled for a sufficient length of time, are ground, and from which they pass through a pipe, I, to the same end ot the train of twin pipes F F with which the pipe Gis connected, but G connects with the upper and I with the lower compartment of the pipe F,

which forms this end ofthe train, as shown in Fig. 2. The other end of the train of twin or double pipes F F has connected with it the feed-pipe J and the discharge pipe K,the feedpipe being connected with the upper 'and th,l discharge pipe with the lower compartment of the pipe F which forms that end of The train of pipes F F is inclosed within a casing, W, of brick-work or other nonconducting material,to prevent loss' ot' heat by radiation. 'The construction of these pipes is'shr wa in Fig. 2, where it may be seen that cath has two compari ments or passages. The two compartments have no communicationat all with each other, but the several lower compartments or passages are connected throughout the whole train, and so are the upper compartments or passages, the upper ones being for the passage of the incoming fibrous substances and water, and the lower ones for the discharging pulp. The upper passages are severally numbered in Fig. 2 from l to 8 in the order in which thematerial and water pass through them,l -that numbered 1 being connected with the leed-pipe, and that numbered 8 with the first pipe A of the" boiler-train, which is numbered 9. The pipes of the boiler-train are severally numbered in Fig. 2 from -9 to 16, respectively, in the order in which the circulation through them takes place, the last pipe (numbered 16) being connected with the mill to deliver the boiled material therei nto. The lower passages of the twin pipes F F are numbered from 17 to 24 in the order in which the pulp or macerated material circulates through them on its way to the discharge-pipe K, the pipe I, coming from the mill, connecting with the passage numbered 17, and the discharge-pipe K connecting with the passage numbered 24.

L, Figs. l and 2, is the barrel of the forcepump for feedir` g the straw or other fibrous mater'a` and the necessary quantity of water to produce its circulation through the trains of pipes F F and A A. Mis the piston of sald pump. N and P are the induction and eduction valves, consisting of iiat steel plates fitted to slide in suitable guides against steelfaced seats c a, and having their lower ends beveled to sharp edges to enable them to cut with a ashears-like action against the lower edges o1 .the cpenings in the valve-seats, and

thus sev( r any pieces of straw or other fibrous material that may be in their way as they move downward to close. These valves pass through suitable stuifing-boxes, b b, and are connected with eccentrics or other suitable devices which derive motion from the steamengine or other motor by which the piston of the pump is worked.

The induction pipe Q of the pump is connected with a mixing-chest, in which thestraw or other fibrous material, cut into pieces of about one or two inches in length, is mixed as thoroughly as possible with water b v means of suitable agitators. The feed pipe J is connected with the discharge-outlet ofthe pump.

The mill H may be composed of any suitable system of rubbing-surfaces. As the matter, when it arrives at the mill, has had the gums softened or dissolved, and is in a very different condition from rags, its fibers are easily' rubbed apart, and itis desirable to avoid cutting them. Instead, therefore, ofthe blades or beaters used in the ordinary paper-engines for cutting, scraping, and drawing out the lint or pulp from the rags, I use simply corrugated surfaces having a rotary or other motion by which they are made to rub the iibers apart without cutting them and to rub and wash the softened gums off from the fibers after the latter have been separated.

rlhedischarge-pipe K is fitted withaloaded valve, which may be substantially like an ordinary safety-valve, by which to regulate the discharge of the pulp, and at the same time to preserve the necessary pressure in the macerating apparatus. E represents a box containing such a valve.

. To set the apparatus in opcration,it is first iilled with water only, and after the tire has been lighted the pump L M is worked very slowly, still pumping nothing but water until the temperature in the boiler is near 3000, when the suction-pipe is brought into communication with the mixing-chest, hereinbefore mentioned, to pump in the'mixture ofwater and fibre us material, and its velocity increased to feed the mixture'in a desirable quantity through the upper passages ofthe pipes F F to the boiler and produce a continuous and sufficiently rapid circulation through the latter and a. continuous delivery to the mill. The pressure produced by the pump, `and the pressure ofthe steam or hot water, due to the heat in the boiler, are both instrumental in forcing the material through the mill and from the mill through the lower passages of the several pipes F F to the discharge-pipe, and

the maceratingprocess is perfectly continuous. The fire should be so regulated as to keep the contents of the upper pipes A A at a temperature of about 3300 Fahrenheit, and the circulation should be so regulated by the capacity and speed of the pump and by the areaof the opening ofthe discharge-pipe and load on the valve in the box E, that the time occupied in passing from one end to the other ofthe train of pipes A A, constituting the boiler, will be sufficient to enable the perfect` maceration to be completed by the subsequent operation of the mill, or to be completed in the boiler itself, if for any material it should not be requisite to use a mill. The macerated material or pulp in its further transit through the lower passages of the pipes F F imparts its heat both through the partitions of the said pipes and through the external portions of the said pipes to the incoming material and water, which are passing in the opposite direction through the upper passages of the said pipes, and in this way becomes cooler and cooler as it approaches the discharge-pipe, while the incoming' material and water become hotter and hotter. By this system of twin pipes the temperature of the discharging pulp may be reduced far below 2120 Fahrenheit, and the temperature of the incoming material and water be raised before arriving at the boiler to a temperature not very far below that in the first pipe A of the train which constitutes the boiler. The discharging pulp may be further cooled and its heat further utilized by constructing the said pipe in the form of a coil and placing the said coil in a suitable vessel, through which the water for mixing with the straw before its advent to the suction pipe of the pump is allowed to circulate, and in that 'way the waste of heat may be obviated in the greatest practicable degree. f

I do not conne myself to the particular form or construction of the boiler herein described or to the particular form and construc-v tion of any of the details ofthe apparatus, as such may be varied or modied without departing from the principle of my invention; but

1. The mode of making the macerating process continuous by supplying and discharging the material and the water necessary to effect maceration by means of a continuous forced circulation through the boiler or macerating apparatus effected by apump orits equivalent, substantially as herein speciiied.

2. Saving the heat of the discharging pulp or macerated material by retaining it under pressure after it has left the boiler or lmacerating apparatus, and passing the incoming fibrous material and water in a contrary direction to the discharge through a suitable system of pipes or passages properly arranged in relation to the discharge pipes or passages, substantially as herein described.

3. Forcing the boiled material from the boiler through a mill or other grinding or rubbing apparatus by the combined or simultaneous action of the pump or its equivalent, through which the circulation through the boiler is produced, and of the pressure due to the heat of the steam or water in the boiler, substantially as herein specied.

4. The employment, in the pump by which the circulationthrough the boiler is produced, of cutting-Valves, operating substantially as and for the purpose herein set forth.

5. The employment, for transferring the heat from the discharging to the incoming material, of twin or double pipes F F, substantially as herein described.

AZEL S. LYMAN.

Witnesses:

THos. L. J. DOUGLAS, GEO. W. REED. 

